电动机两回出线供电方式下零序保护分析与应用  

Analysis and application of motor zero sequence protection under two outlet power supply mode

作　　者：马迎东 温强 Ma Yingdong;Wen Qiang(Shenhua Funeng Power Generation Co.,Ltd,Quanzhou,Fujian 362000;Changchun Shuangyang Power Supply Co.,Ltd,Changchun 130000)

机构地区：[1]神华福能发电有限责任公司,福建泉州362000 [2]长春市双阳区供电有限责任公司,长春130000

出　　处：《电气技术》2020年第1期126-128,132,共4页Electrical Engineering

摘　　要：本文以发电厂厂用电大容量电动机采用不同回数出线供电方式为背景,分析在两回出线供电发生接地故障时一次零序电流情况,并与单回出线供电方式进行对比分析,得出一次总零序电流与供电出线回数无关的结论。在此基础上,分析计算两回出线供电方式下,零序保护电流互感器二次侧分别采用串、并联接线方式时保护装置采集零序电流的公式,利用负载阻抗与励磁阻抗和漏电抗之和不同时的对比,给出二次侧最优接线方式。同时在零序保护整定时,给出二次侧两种接线方式下定值整定过程中的注意事项,以提高零序保护运行可靠性。Based on the background of double-circuit power supply mode for large-capacity motor used in power plant,the primary current and series-parallel connection mode of secondary side of zero-sequence current transformer(CT)under grounding condition are analyzed,and the optimal connection mode of secondary side is given by comparing load impedance with excitation impedance and leakage reactance at the same time when setting zero-sequence protection.In order to improve the reliability of zero sequence protection,the precautions for setting the two wiring modes are put forward.

关 键 词：零序保护 励磁阻抗 漏电抗 电流互感器 

分 类 号：TM32[电气工程—电机]